The floor of the cranial cavity is divided into three distinct depressions. They are known as the anterior cranial fossa, middle cranial fossa and posterior cranial fossa. Each fossa accommodates a different part of the brain

1. Anterior Cranial fossae

2. Contents
• Introduction
• Boundaries
• Anterior Cranial Fossae
• Clinical Correlates
• Summary
• MCQs
• References

3. Base of skull divide into
Anterior cranial fossae
Middle cranial fossae
Posterior cranial fossae

4. 1. Posterior border of lesser wing of sphenoid
2. Anterior border of sulcus chiasmaticus in
median region
Anterior and middle cranial fossae separated by

5. Boundaries of anterior cranial fossae
Anterior & lateral - Frontal bone
Floor – By three bone
1. Cribriform plate of ethmoid
2. Orbital plate of frontal bone
3. Lesser wing with jugum
sphenoidale of sphenoid bone

7. Foramen & Structure
1. Cribriform plate - Olfactory nerve
2. Anterior ethmoidal canal -Anterior
ethmoidal nerve & vessels
3. Posterior ethmoidal canal- Posterior
ethmoidal nerve & vessels
4. Crista galli

8. Ossification
• Crista galli begins to ossify from tip at 3 months in
IUL and is usually ossified by first year.
Most of anterior skull base, including cribriform
plates, are ossified after 2 years of birth

9. Midline sagittal reformation of CT scan
Foramen cecum (FC)
Crista galli (CG)
Cribriform plate (CP)
Planum sphenoidale (PS)

10. Clinical Aspect

11. Midline frontal bone fracture
Fractures involving
1. Orbital roof
2. Cribriform plate
3. Supraorbital nerve injury
4. Fractures of posterior wall of
frontal sinus
•Cerebrospinal fluid (CSF) rhinorrhea
5. Complete bitemporal hemianopia
Treatment
Removal of posterior wall and all frontal sinus
mucosa, typically through a frontal
craniotomy approach

12. MCQ’s
A conical projection grows upward from the cribriform
plate is called as crista galli and at what age it is ossified?
• 3rd month after birth
• First year after birth
• 3rd month in IUL
• 6th month in IUL
First year after birth

13. Name the structure which passes from below
A marked area.
• Olfactory nerve
• Anterior ethmoidal nerve
• Posterior ethmoidal nerve
• Emissary vein
A
Olfactory nerve

14. • A severe RTA accident case came to an emergency
department. To rule out any fracture doctor suggest
X- ray of skull. Which shows a midline frontal fracture
(as shown in given image) and patient has a blood-
stained discharge of CSF from nose (CSF rhinorrhea).
• What is cause for the discharge of CSF from nose?
Cribriform plate fracture
Human osteology by AK Datta 3rd edition , pg no 116

15. References
• Gray's Anatomy_ The Anatomical Basis of
Clinical Practice, 41e
• Essential of human osteology ,2nd edition by
A.K. Datta

16. Thank You